Geomorphology of the Kaikoura area. (1968)
AuthorsChandra, Satishshow all
The Kaikoura Area comprises 64 square miles of low-lying land on the north-east coast of South Island, New Zealand. The major physiographic units are the Peninsula Block, Beach Ridges and Raised Beaches, Hard Rock Areas and the Alluvial Fans. The upper two erosion surfaces on the Peninsula Block are the result of stillstands during the tectonic uplift with marine processes effectively cutting shore platforms. These events took place before the penultimate interglacial. The third and fourth erosion surfaces have correlative subsurface deposits of Terangian and Oturian Interglacial Stages. On the piedmont alluvial plain large areas of Otiran Stage fan surfaces are present but Holocene sedimentation has destroyed much of the original topography. The strandlines south of the Kaikoura Peninsula are the result of falling sealevel after the post-glacial high. Areas of post-glacial marine aggradation backed by post-glacial cliffs are present around the Kaikoura Peninsula. Cliffing by marine processes of the Hapuku delta-fan edge was initiated with the onset of rising sealevel after the last glaciation. Material delivered to the beach had a net longshore transportion southwards leading to the formation of a barrier spit. On a regional scale the most significant geoomorphic change in terms of dimensions from Pre-Late Pleistocene to present day has been the progradation of coastline from the Seaward Kaikoura Mountain Front to its present position.